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Android Trace Issue

See original GitHub issue

Issue Description

Hello, I am using raptor_frida_android_trace.js and I am getting an error upon the app being spawned.

Spawned APP. Resuming main thread! [DEVICE::APP]-> TypeError: cannot read property 1 of null at [anon] (duk_hobject_props.c:2385) at [anon] (repl1.js:46) at frida/node_modules/frida-java/index.js:190 at forEach (native) at d (java.js:2216) at frida/node_modules/frida-java/index.js:120 at trace (repl1.js:51) at [anon] (repl1.js:174) at frida/node_modules/frida-java/lib/vm.js:39 at v (frida/node_modules/frida-java/index.js:338) at frida/node_modules/frida-java/index.js:309 [...]

It looks like the issue is on line 46: var className = aClass.match(/[L](.*);/)[1].replace(/\//g, ".");

Is there an easy fix like a null check? Could this issue be caused by obfuscation?

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:5 (1 by maintainers)

github_iconTop GitHub Comments

h3rb0commented, Jun 28, 2019

I guess the code var className = aClass.match(/[L](.*);/)[1].replace(/\//g, "."); is just used for extract the class name from aClass “;”. but in my case, the value of aClass is “”. Therefor , just
var className = aClase;

leoandrade20commented, Jan 21, 2021

Hello, I’m trying to display a Toast message through Frida with this code:

Java.perform(() => {
     var context = Java.use("").currentApplication().getApplicationContext();
     Java.scheduleOnMainThread(function() {
          var toast = Java.use("android.widget.Toast");
          toast.makeText(context, Java.use("java.lang.String").$new("Hellooo !!"), 1).show();

However, I still get the error: TypeError: cannot read property 'getApplicationContext' of null

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